1. Field of the Disclosure
The present disclosure relates to an intake manifold for an internal combustion engine. The inventive intake manifold has the ability to control the motion of charge air passing through the manifold.
2. Related Art
The ability to control pre-combustion charge motion of air entering the cylinders of an internal combustion engine has grown appreciably more important as emissions standards and fuel economy requirements have become increasingly more stringent. Although it is known to employ charge motion control devices and intake runner control valves with internal combustion engines, such devices typically increase the complexity and package volume of an engine by necessitating their placement within a spacer located between the upper and lower intake manifolds, for example. This type of construction is shown in FIG. 4, in which a spacer, 102, containing airflow control elements 103, is mounted between an upper intake manifold, 104, and a cylinder head or lower intake manifold (not shown). Other known charge motion control devices include a control shaft journaled within an oversized mounting flange. In this construction, a separate retainer plate, secured in place with threaded fasteners, maintains the control shaft in place. This construction, too, is characterized by undesirable expanded package volume and complexity, as well as excessive cost.
It would be desirable to provide charge air motion control with an intake manifold that does not require either an additional component such as a spacer having a built-in charge motion control device, or added package volume which increases the installed space required by the intake system of an engine.